Furniture, Wood and Cabinetry Finishing - painting wood furniture

I am refinishing an old bedroom suite (originally painted in 1920's). I've stripped it and put several coats of Kilz 2 primer on with an air sprayer. The primer turned out pretty good and smooth after sanding with 320 grit. I tried spraying on Behr semi-gloss latex for color - but it ended up gritty on the surface and when I sanded, it all just came off (not the primer though - just color latex). I then read on the can not to use an air sprayer. Someone suggested that I should stick to a brush, but in the past, it seems to not level well and I want a smooth finish like the factory original finish. Any suggestions as to the paint I should use? Use Floetrol? I understand Behr doesn't level well. Someone suggested BM waterbourne enamal? Can I put that on top of what latex is on already?
Also, for the final coat, do I still sand the final finish with a 400 grit? Won't it still leave some marring?
Thanks! I'm an amateur, but want to do this right.

BM, Valspar, Sherwin-Williams are good. Behr paint gets a lot of bad press, I would skip it. I like Valspar paint for furniture. Sometimes, I thin it 10% with water for spraying. It all depends upon the particular can of paint and the complexity of the surface. The final coat of paint should be left on its own for 4 - 7 days to be sure that it hardens properly before putting it to use.

Sanding 180 between coats of primer and 240 between coats of paint has given me good results. Leave the last coat unsanded.

Hope this helps.

Thanks for you help. Do I continue with a latex? Is enamel different than latex? Should I use an oil as I want this to last many years? What kind of paint besides manufacturer should I use?
Thanks!

Latex is a good paint. Alkyd paint is harder and a bit more likely to chip. Probably the same in the long run, if you can wait for the alkyd to dry and don' t mind the cleanup.

I have latex painted pieces that are many years old and doing quite well.

I like American Traditions by Valspar.